Metalink Downloader for Chrome

[Sundaram]

Hey,

This is Sundaram. I have written a small extension that helps you
download metalinks in Chrome. Since metalinks are not supported by
Chrome natively, this helps in downloading files pointed by the
metalinks.

In essence, the extension does the following

1. Detect all metalinks in the current tab - filtered based on <a> tag
and .metalink extension
2. Based on user selections, download the metalink file using
XMLHttpRequest
3. Parse the response from XHR and get the file to be downloaded and
its *source mirror*.
4. Download the file from the most preferred source and save it.
5. In case of errors, redownload the file.

For downloading the file, I use the chrome experimental downloads API.
However, there are a number of limitations with the API.

1. For example, I would have to checksum the file using XHR and
download the file using experiemental downloads API. This means the
same file would have to be downloaded twice to check for errors in the
data.
2. Metalinks provide infomation about multiple mirrors. Thus, multi-
sourced downloads is theoretically possible. However, the downloads
API does not have options for that.
3. If a particular piece is erroneous, the API does not allow you to
download the piece alone from another mirror.

Basically, what the extension does is really really minimal and we
would want to expand on it to make use of all the advantages of
metalinks.

So, I was wondering if NPAPI plugins would solve all these issues. I
haven't developed one before. But, I do know that you get a lot more
control with the plugin as you are not extending the browser's
functionality as in the case of extensions.

Has anyone worked on a download manager with NPAPI before?

Information on how the extension was developed and what the future
steps are can be found here.
http://thesundaram.wordpress.com/

Thanks.

[Ant Bryan]

Metalink Downloader is pretty feature complete.

try it out!

http://code.google.com/p/metalink-chrome-extension/

Metalinks contain information (like mirrors & hashes) about downloads so that advanced features can be automated. Metalinks are frequently used for large downloads and files on mirror networks/CDNs. For example, Metalinks for openSUSE contain information about the OpenSUSE ISO disk image so the download process will be simpler. This information helps in variety of ways, such as checksumming (error detection & repair), mirror failover & download resuming, multi-sourced downloads, mirror priorities, p2p integration, & so on.